1. Field of the Invention
This invention relates to the field of electrical switches. The invention relates to a device for operating multiple electrical switches, and more specifically to a device for operating electrical switches controlling marine power units, such as bow and stern thrusters and other propulsion units for boats.
2. Description of the Related Art
Bow and stern thrusters have for several years been used as a means for maneuvering large and small watercraft in situations where the watercraft speed is too low to enable adequate rudder control. Particularly in connection with docking and setting off, or other low speed operations, have such thrusters proven very useful.
Bow and stern thrusters may be electrically or hydraulically driven, and have traditionally been controlled by means of various joystick configurations mounted on the boat control panel, and operated by the person actually steering the boat.
More recently, such bow thrusters and also stern thrusters have become more commonplace on smaller vessels, such as pleasure boats down to approximately 20 feet. As public marinas are becoming more crowded, more and more pleasure boat owners are relying on lateral thrusters to avoid damages and accidents in connection with docking and setting off.
As mentioned, thrusters are commonly controlled and operated by means of various joystick arrangements. One configuration as shown in FIG. 2b consists of a dual joy stick unit 20; one joy stick 22 providing lateral bow control and one joy stick 24 controlling the stern thruster. Another configuration as shown in FIG. 2a employs a single joystick 26 with a switch 28 mounted on top of the joystick 26. The operator may then switch back and forth between forward and aft thrusters.
Common problems with the known existing joystick arrangements are that they may be awkward to operate and not configured entirely logically in regards the actual resulting boat motion. Existing configurations and arrangements may be particularly difficult to operate for the often little experienced pleasure boat owner.
In situations involving for example strong winds, heavy waves or swell, poor visibility, darkness; particularly the lesser experienced pleasure boat owner is prone to making mistakes in operating the thruster, mistakes which close to quayside, shore or other boats may cause substantial damage and lead to hazardous scenarios.
It is therefore a long felt need for a boat manoeuvring control unit which is easy and logical to use even for the inexperienced boater, has a shape and function which is fail safe and xe2x80x9cfool proofxe2x80x9d even in the most adverse conditions, and is technically reliable.
The present invention solves the above need, in that it provides a novel means for controlling multiple electrical switches, such as marine boat manoeuvring control switches. It furthermore alleviates the need for multiple joysticks in order to control the thrusters. The boat manoeuvring control unit in accordance with the invention is based on field proved technology, but has a shape and function which is fail safe and xe2x80x9cfool proofxe2x80x9d even in the most adverse conditions, is easy and logical to use even for the inexperienced boater and is technically reliable.
These and other objects and features of the invention are provided by a control unit which comprises a boat shaped, or navicular, control knob mounted over a switch panel affixed to a base plate. The boat shape is essential, in that the shape and function of this knob is logical, fail safe and xe2x80x9cfool proofxe2x80x9d even in the most adverse conditions, and is easy to use even for the inexperienced boater.
The base plate lower housing is of a standard size and fits standard control panels. The switch panel has a number of boat manoeuvring control switches, either micro switches or switches embedded in the panel, below a sealing film.
The navicular control knob is fastened to a pair of guide elements riding on each end of a pin which extends through a plug mounted on the base plate. The control knob is thus movable in a horizontal plane over the switch panel.
More specifically, the boat manoeuvring control unit comprises:
a base plate having a socket, a lower housing, and attachment means;
a switch panel mounted on the base plate, where the switch panel has a plug receiving aperture, a number of on/off switches, and a number of control switch means; and
a boat shaped, or navicular, control knob mounted on the base plate and being displaceable over the panel, and where the control knob has a plurality of engagement means.
Furthermore, the control knob is mounted on the base plate by means of:
a plug, having a longitudinal bore for slidably receiving a coil spring, and where the plug lower structure extends through the aperture and is mounted in the socket; and
a pair of forward and aft guide elements mounted on the outer ends of forward and aft plug pins and engaging the engaging means respectively.
As an option, the coil spring may be guided by means of a guide pin, coaxially located within the spring.
As an option, two separate plug springs could be employed, but it has been found advantageous to have only one plug spring extending through the plug bore. One plug spring facilitates an easier transverse movement and contributes in a favourable manner to keeping one knob end stationary, when the other is being moved. Such movement of a first control knob end will compress the plug spring axially and thus increase the pressure of the plug pin at the second end, which in turn applies a pressure towards its associated guide element; contributing to keeping the second end in a stationary position.
Each of the guide elements carry an actuator peg, generally vertically oriented. A spring biases the peg in downward direction, such that the peg is held in a position proximal to the panel. The control knob may be horizontally aligned with the switch panel by means of a number of stabilising knobs which are disposed symmetrically along the control knob lower edge, being proximal with the said panel.
The control knob and guide element assembly is movably attached to the plug by means of forward and aft plug pins being longitudinally aligned with said plug and where the plug pins have outer ends each being movably received into respective ones of forward and aft guide element cavities, and the plug pins have inner bores for receiving opposite ends of the coil spring and optionally the guide pin. The plug pins, optional guide pin and spring are slidably disposed in the plug longitudinal bore.
In a non-actuated state, the navicular control knob remains in a neutral position in which position no one of the control switches are operated.
When the control knob is selectively and manually moved in a horizontal plane, the forward and aft actuator pegs are also moved to selective locations over or near the afore mentioned control switches. The peg downward acting forces activate the switches correspondingly by depression or other form of impact.
Due to certain geometric features of the guide element, plug and pins, the control knob may selectively be displaced about either end while the other end remains at rest, the knob may be rotated, and the knob automatically returns to a neutral position released.
Other preferred embodiments are described by the accompanying independent claims.
By means of the invented control unit, any boat propulsion unit, such as bow and stern thrusters, may be controlled by a method to be described in the detailed description.